Isolation and characterization of mitochondrial DNA from the alkane yeast Saccharomycopsis lipolytica

Summary Mitochondrial (mt) DNA of the alkane yeast, Saccharomycopsis lipolytica, was isolated. Its buoyant density in CsCl was found to be of 1.687 g/cm³, indicating a GC content of 27.5% and its melting point T_m = 79.5 °C, indicating a GC content of 24.9%. The corresponding values for nuclear (n) DNA, are 1.709 g/cm³ (GC: 49.5%) and T_m = 90.5 (GC: 51.7%) respectively. Electron microscopy revealed that mtDNA has a circular structure with a contour length of about 14.5 µm corresponding to 45.5 kb per molecule. The size estimated from restriction analyses performed with 7 endonucleases was 48.35 kb/molecule. A restriction map was constructed, using the cleavage data of 4 endonucleases.